A family's house was gutted and their beloved dog killed when a Nutella jar magnified the sun's rays, sparking a huge blaze.

Declan Murphy has warned others to be alert to the danger following the devastating inferno at his home in Fielding Avenue, Twickenham, on Sunday afternoon (February 15).

The fire is believed to have been been ignited when the low winter sunlight was focused through the chocolate spread container on his daughter's bedroom window sill, used to hold her loom bands.

Mr Murphy was out at the time, celebrating the anniversary of his engagement, with his wife and two children, aged seven and three. But their dog, a nine-year-old Jack Russell called Chili, was trapped inside and died of smoke inhalation.

"We're all heartbroken at Chili's death and we've been told it will be up to a year before the house is ready for us to move back into," said the 41-year-old electrical supervisor.

"I want to ensure other people are aware of the dangers and know to keep glass items away from windows and out of direct sunlight so they don't have to go through anything like this."

Declan Murphy with his wife Lindsay, daughter Kyra and son Coen

Four fire engines and 21 firefighters attended the blaze, which destroyed the roof and seriously damaged the first floor, after being called just after 2.30pm.

The fire came just days before sunlight refracted off a mirror table at the Mayfair home of lingerie tycoon Michelle Mone, setting alight a bean bag, on Thursday (February 19).

"Crystal and glass ornaments and items such as mirror tables should be kept out of direct sunlight. We wouldn’t advise that people put fires out themselves but it is good to see that Ms Mone is not injured.

"This shows these fires are not an urban myth.

"Also make sure that you have a working smoke alarm on every level of your home."